https://github.com/cilium/cilium
Tip revision: 5d3899fbafa55958709083badeae0b19903da68a authored by Joe Stringer on 28 April 2023, 20:23:52 UTC
Prepare for release v1.14.0-snapshot.2
Prepare for release v1.14.0-snapshot.2
Tip revision: 5d3899f
tc_egressgw_snat.c
// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
/* Copyright Authors of Cilium */
#include "common.h"
#include <bpf/ctx/skb.h>
#include "pktgen.h"
#include "config_replacement.h"
/* Set ETH_HLEN to 14 to indicate that the packet has a 14 byte ethernet header */
#define ETH_HLEN 14
/* Enable code paths under test */
#define ENABLE_IPV4
#define ENABLE_NODEPORT
#define ENABLE_EGRESS_GATEWAY
#define ENABLE_MASQUERADE
#define ENCAP_IFINDEX 0
#define CLIENT_IP v4_pod_one
#define CLIENT_PORT __bpf_htons(111)
#define EXTERNAL_SVC_IP v4_ext_one
#define EXTERNAL_SVC_PORT __bpf_htons(1234)
#define NODE_IP v4_node_one
#define EGRESS_IP IPV4(1, 2, 3, 4)
#define SECCTX_FROM_IPCACHE 1
static volatile const __u8 *client_mac = mac_one;
static volatile const __u8 *ext_svc_mac = mac_two;
#include "bpf_host.c"
#define TO_NETDEV 0
#define FROM_NETDEV 1
struct {
__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
__uint(key_size, sizeof(__u32));
__uint(max_entries, 2);
__array(values, int());
} entry_call_map __section(".maps") = {
.values = {
[TO_NETDEV] = &cil_to_netdev,
[FROM_NETDEV] = &cil_from_netdev,
},
};
static __always_inline int egressgw_snat_pktgen(struct __ctx_buff *ctx, bool reply)
{
struct pktgen builder;
struct tcphdr *l4;
struct ethhdr *l2;
struct iphdr *l3;
void *data;
/* Init packet builder */
pktgen__init(&builder, ctx);
/* Push ethernet header */
l2 = pktgen__push_ethhdr(&builder);
if (!l2)
return TEST_ERROR;
if (reply)
ethhdr__set_macs(l2, (__u8 *)ext_svc_mac, (__u8 *)client_mac);
else
ethhdr__set_macs(l2, (__u8 *)client_mac, (__u8 *)ext_svc_mac);
/* Push IPv4 header */
l3 = pktgen__push_default_iphdr(&builder);
if (!l3)
return TEST_ERROR;
if (reply) {
l3->saddr = EXTERNAL_SVC_IP;
l3->daddr = EGRESS_IP;
} else {
l3->saddr = CLIENT_IP;
l3->daddr = EXTERNAL_SVC_IP;
}
/* Push TCP header */
l4 = pktgen__push_default_tcphdr(&builder);
if (!l4)
return TEST_ERROR;
if (reply) {
/* Get the destination port from the NAT entry. */
struct ipv4_ct_tuple tuple = {
.saddr = CLIENT_IP,
.daddr = EXTERNAL_SVC_IP,
.dport = EXTERNAL_SVC_PORT,
.sport = CLIENT_PORT,
.nexthdr = IPPROTO_TCP,
};
struct ipv4_nat_entry *nat_entry = __snat_lookup(&SNAT_MAPPING_IPV4, &tuple);
if (!nat_entry)
return TEST_ERROR;
l4->source = EXTERNAL_SVC_PORT;
l4->dest = nat_entry->to_sport;
} else {
l4->source = CLIENT_PORT;
l4->dest = EXTERNAL_SVC_PORT;
}
data = pktgen__push_data(&builder, default_data, sizeof(default_data));
if (!data)
return TEST_ERROR;
/* Calc lengths, set protocol fields and calc checksums */
pktgen__finish(&builder);
return 0;
}
static __always_inline int egressgw_snat_check(const struct __ctx_buff *ctx, bool reply,
__u64 tx_packets, __u64 rx_packets)
{
void *data, *data_end;
__u32 *status_code;
struct tcphdr *l4;
struct ethhdr *l2;
struct iphdr *l3;
test_init();
data = (void *)(long)ctx_data(ctx);
data_end = (void *)(long)ctx->data_end;
if (data + sizeof(__u32) > data_end)
test_fatal("status code out of bounds");
status_code = data;
assert(*status_code == CTX_ACT_OK);
l2 = data + sizeof(__u32);
if ((void *)l2 + sizeof(struct ethhdr) > data_end)
test_fatal("l2 out of bounds");
l3 = (void *)l2 + sizeof(struct ethhdr);
if ((void *)l3 + sizeof(struct iphdr) > data_end)
test_fatal("l3 out of bounds");
l4 = (void *)l3 + sizeof(struct iphdr);
if ((void *)l4 + sizeof(struct tcphdr) > data_end)
test_fatal("l4 out of bounds");
if (reply) {
if (memcmp(l2->h_source, (__u8 *)ext_svc_mac, ETH_ALEN) != 0)
test_fatal("src MAC is not the external svc MAC")
if (memcmp(l2->h_dest, (__u8 *)client_mac, ETH_ALEN) != 0)
test_fatal("dst MAC is not the client MAC")
if (l3->saddr != EXTERNAL_SVC_IP)
test_fatal("src IP has changed");
if (l3->daddr != CLIENT_IP)
test_fatal("dst IP hasn't been revSNATed to client IP");
} else {
if (memcmp(l2->h_source, (__u8 *)client_mac, ETH_ALEN) != 0)
test_fatal("src MAC is not the client MAC")
if (memcmp(l2->h_dest, (__u8 *)ext_svc_mac, ETH_ALEN) != 0)
test_fatal("dst MAC is not the external svc MAC")
if (l3->saddr != EGRESS_IP)
test_fatal("src IP hasn't been NATed to egress gateway IP");
if (l3->daddr != EXTERNAL_SVC_IP)
test_fatal("dst IP has changed");
}
/* Lookup the SNAT mapping for the original packet to determine the new source port */
struct ipv4_ct_tuple tuple = {
.daddr = CLIENT_IP,
.saddr = EXTERNAL_SVC_IP,
.dport = EXTERNAL_SVC_PORT,
.sport = CLIENT_PORT,
.nexthdr = IPPROTO_TCP,
.flags = TUPLE_F_OUT,
};
struct ct_entry *ct_entry = map_lookup_elem(get_ct_map4(&tuple), &tuple);
if (!ct_entry)
test_fatal("no CT entry found");
if (ct_entry->tx_packets != tx_packets)
test_fatal("bad TX packet count (expected %u, actual %u)",
tx_packets, ct_entry->tx_packets)
if (ct_entry->rx_packets != rx_packets)
#ifdef ISSUE_25110_FIXED
/* This test fails until this issue is fixed:
* https://github.com/cilium/cilium/issues/25110
*/
test_fatal("bad RX packet count (expected %u, actual %u)",
rx_packets, ct_entry->rx_packets)
#else
;
#endif
tuple.saddr = CLIENT_IP;
tuple.daddr = EXTERNAL_SVC_IP;
struct ipv4_nat_entry *nat_entry = __snat_lookup(&SNAT_MAPPING_IPV4, &tuple);
if (!nat_entry)
test_fatal("could not find a NAT entry for the packet");
if (reply) {
if (l4->source != EXTERNAL_SVC_PORT)
test_fatal("src port has changed");
if (l4->dest != CLIENT_PORT)
test_fatal("dst TCP port hasn't been revSNATed to client port");
} else {
if (l4->source != nat_entry->to_sport)
test_fatal("src TCP port hasn't been NATed to egress gateway port");
if (l4->dest != EXTERNAL_SVC_PORT)
test_fatal("dst port has changed");
}
test_finish();
}
/* Test that a packet matching an egress gateway policy on the to-netdev program
* gets correctly SNATed with the egress IP of the policy.
*/
PKTGEN("tc", "tc_egressgw_snat1")
int egressgw_snat1_pktgen(struct __ctx_buff *ctx)
{
return egressgw_snat_pktgen(ctx, false);
}
SETUP("tc", "tc_egressgw_snat1")
int egressgw_snat1_setup(struct __ctx_buff *ctx)
{
struct egress_gw_policy_key in_key = {
.lpm_key = { EGRESS_PREFIX_LEN(24), {} },
.saddr = CLIENT_IP,
.daddr = EXTERNAL_SVC_IP & 0Xffffff,
};
struct egress_gw_policy_entry in_val = {
.egress_ip = EGRESS_IP,
.gateway_ip = NODE_IP,
};
map_update_elem(&EGRESS_POLICY_MAP, &in_key, &in_val, 0);
/* Jump into the entrypoint */
tail_call_static(ctx, &entry_call_map, TO_NETDEV);
/* Fail if we didn't jump */
return TEST_ERROR;
}
CHECK("tc", "tc_egressgw_snat1")
int egressgw_snat1_check(const struct __ctx_buff *ctx)
{
return egressgw_snat_check(ctx, false, 1, 0);
}
/* Test that a packet matching an egress gateway policy on the from-netdev program
* gets correctly revSNATed and connection tracked.
*/
PKTGEN("tc", "tc_egressgw_snat2_reply")
int egressgw_snat2_reply_pktgen(struct __ctx_buff *ctx)
{
return egressgw_snat_pktgen(ctx, true);
}
SETUP("tc", "tc_egressgw_snat2_reply")
int egressgw_snat2_reply_setup(struct __ctx_buff *ctx)
{
/* Jump into the entrypoint */
tail_call_static(ctx, &entry_call_map, FROM_NETDEV);
/* Fail if we didn't jump */
return TEST_ERROR;
}
CHECK("tc", "tc_egressgw_snat2_reply")
int egressgw_snat2_reply_check(const struct __ctx_buff *ctx)
{
return egressgw_snat_check(ctx, true, 1, 1);
}
PKTGEN("tc", "tc_egressgw_snat3")
int egressgw_snat3_pktgen(struct __ctx_buff *ctx)
{
return egressgw_snat_pktgen(ctx, false);
}
SETUP("tc", "tc_egressgw_snat3")
int egressgw_snat3_setup(struct __ctx_buff *ctx)
{
/* Jump into the entrypoint */
tail_call_static(ctx, &entry_call_map, TO_NETDEV);
/* Fail if we didn't jump */
return TEST_ERROR;
}
CHECK("tc", "tc_egressgw_snat3")
int egressgw_snat3_check(struct __ctx_buff *ctx)
{
int ret = egressgw_snat_check(ctx, false, 2, 1);
struct egress_gw_policy_key in_key = {
.lpm_key = { EGRESS_PREFIX_LEN(24), {} },
.saddr = CLIENT_IP,
.daddr = EXTERNAL_SVC_IP & 0Xffffff,
};
/* Remove the policy to eliminate interference with other tests. */
map_delete_elem(&EGRESS_POLICY_MAP, &in_key);
return ret;
}
/* Test that a packet matching an excluded CIDR egress gateway policy on the
* to-netdev program does not get SNATed with the egress IP of the policy.
*/
PKTGEN("tc", "tc_egressgw_skip_excluded_cidr_snat")
int egressgw_skip_excluded_cidr_snat_pktgen(struct __ctx_buff *ctx)
{
return egressgw_snat_pktgen(ctx, false);
}
SETUP("tc", "tc_egressgw_skip_excluded_cidr_snat")
int egressgw_skip_excluded_cidr_snat_setup(struct __ctx_buff *ctx)
{
struct egress_gw_policy_key in_key = {
.lpm_key = { EGRESS_PREFIX_LEN(24), {} },
.saddr = CLIENT_IP,
.daddr = EXTERNAL_SVC_IP & 0Xffffff,
};
struct egress_gw_policy_entry in_val = {
.egress_ip = 0,
.gateway_ip = NODE_IP,
};
map_update_elem(&EGRESS_POLICY_MAP, &in_key, &in_val, 0);
struct egress_gw_policy_key in_key_excluded_cidr = {
.lpm_key = { EGRESS_PREFIX_LEN(32), {} },
.saddr = CLIENT_IP,
.daddr = EXTERNAL_SVC_IP,
};
struct egress_gw_policy_entry in_val_excluded_cidr = {
.egress_ip = 0,
.gateway_ip = EGRESS_GATEWAY_EXCLUDED_CIDR,
};
map_update_elem(&EGRESS_POLICY_MAP, &in_key_excluded_cidr, &in_val_excluded_cidr, 0);
/* Jump into the entrypoint */
tail_call_static(ctx, &entry_call_map, TO_NETDEV);
/* Fail if we didn't jump */
return TEST_ERROR;
}
CHECK("tc", "tc_egressgw_skip_excluded_cidr_snat")
int egressgw_skip_excluded_cidr_snat_check(const struct __ctx_buff *ctx)
{
void *data, *data_end;
__u32 *status_code;
struct tcphdr *l4;
struct ethhdr *l2;
struct iphdr *l3;
test_init();
data = (void *)(long)ctx_data(ctx);
data_end = (void *)(long)ctx->data_end;
if (data + sizeof(__u32) > data_end)
test_fatal("status code out of bounds");
status_code = data;
assert(*status_code == CTX_ACT_OK);
l2 = data + sizeof(__u32);
if ((void *)l2 + sizeof(struct ethhdr) > data_end)
test_fatal("l2 out of bounds");
l3 = (void *)l2 + sizeof(struct ethhdr);
if ((void *)l3 + sizeof(struct iphdr) > data_end)
test_fatal("l3 out of bounds");
l4 = (void *)l3 + sizeof(struct iphdr);
if ((void *)l4 + sizeof(struct tcphdr) > data_end)
test_fatal("l4 out of bounds");
if (memcmp(l2->h_source, (__u8 *)client_mac, ETH_ALEN) != 0)
test_fatal("src MAC is not the client MAC")
if (memcmp(l2->h_dest, (__u8 *)ext_svc_mac, ETH_ALEN) != 0)
test_fatal("dst MAC is not the external svc MAC")
if (l3->saddr != CLIENT_IP)
test_fatal("src IP has changed");
if (l3->daddr != EXTERNAL_SVC_IP)
test_fatal("dst IP has changed");
if (l4->source != CLIENT_PORT)
test_fatal("src TCP port has changed");
if (l4->dest != EXTERNAL_SVC_PORT)
test_fatal("dst port has changed");
/* Delete the excluded CIDR entry otherwise other tests may fail as this
* entry will persist across the different tests.
*/
struct egress_gw_policy_key in_key_excluded_cidr = {
.lpm_key = { EGRESS_PREFIX_LEN(32), {} },
.saddr = CLIENT_IP,
.daddr = EXTERNAL_SVC_IP,
};
map_delete_elem(&EGRESS_POLICY_MAP, &in_key_excluded_cidr);
test_finish();
}